Difference Between Fuse and MCB (Miniature Circuit Breaker)

The MCB and a normal fuse have the same function. Both, are used to prevent the circuit from an excess flow of current resulted due to short circuit or overload. When the current flow exceeds a fuse wire burns out in order to open the circuit. Where an MCB disconnects the circuits by tripping

MCB (miniature circuit breaker)

• MCB is an electromagnetic device. It works by moving a switch mechanism with an electromagnetic force developed from a solenoid.
• MCB’s are sensitive than the fuse.
• MCB’s are easy to restart after the tripping as it has no any replacing parts. Just a switching like a normal switch can reset the circuit. It is feasible for the common users and the circuit can be closed within no time.

• MCB’s gives safe protection because it has a perfect package with an enclosed case. So it can ensure complete isolation.

• MCB’s are long lasting.

• Comparing with conventional fuse, the MCB’s are costly.

• MCB’s are compact in place by hiding the wires and current carrying points.

• MCB’s can be identified directly whether it is closed or open by the position of switching knob.

Conventional Fuse

• Fuses are a sacrificial part which works by melting conductor itself.
• Fuses require replacing of the fuse wire in order to close the circuit after burn out. It takes time and not as easy as MCB and also it requires tools for replacing.

• As the one terminal of the fuse base has live point, the replacing is not safe. And if the problem is due to a short circuit or overload that has not fixed properly a sudden spark may occur during the placing of the fuse. The refixing should be performed by a skilled one as it is not safe for a common user.

• Fuse is not compact to isolate the current carrying points from the user. Any improper human contact to live points may chance to get an electric shock.

• The exact size of wire or ampere rating is required for the proper working of a fuse. If the rating does not match with the load limit, it results in non-disconnection or pre-disconnection of the fuse. Where a case of non-disconnection may cause further electrical accidents and pre-disconnection cause unwanted interruptions.

• Fuses are very cheaper compared to MCB’s.